Mass transportation systems have been developed and proposed for a variety of transportation vehicles. In one example, the system uses vehicles which are carried by a cable or track and which stop for passenger or cargo pick-up and drop-off automatically upon demand which is made known to the system by either human input of some type or computer program. Such systems have been used and proposed for use in high traffic density situations. These systems have been designed for relatively low-speed operations and for relatively short distance applications such as within airports and in downtown areas. Vehicles for such systems have been carried on tracks or guideways. Switching of vehicles from track to track or guideway to guideway has generally been accomplished by employing movable track or guideway elements. Vehicles designed for such use may be used only on the tracks or guideways for which they are designed. Use of the tracks or guideways is also restricted to system captive vehicles designed only for track or guideway use. Some limited-use vehicles have been designed for dual road and track use under manual control. Examples of such a vehicle are normal road use trucks equipped with separate wheels to allow them to be driven by railroad maintenance personnel along railroad tracks under manual control. Some normal road-use automobiles have been adapted with either mechanical steering arms designed to cause the car to follow a steering rail mounted along a special roadway, or electronic sensors designed to cause the car to follow magnets or electrified wires embedded in road pavement. Several disadvantages are inherent in these past systems:
1. Some of the systems are capable of providing service only between stations and are incapable of providing door-to-door service to passengers and cargo.
2. Systems designed to allow specially equipped automobiles to operate on automated guideways have not provided on-demand or scheduled station-to-station service for non-automobile passengers.
3. Inability to provide door-to-door service for passengers and cargo greatly restricts the usefulness of station-to-station systems that use track or guideway only vehicles. Provision of such systems makes it necessary to employ other means such as conventional automobiles or trucks either instead of or in addition to the system. Such automobiles and trucks cause pollution of the atmosphere and require expensive and usually parallel networks of roads and highways.
4. In order to enable operation under the full range of weather conditions, track or guideway based systems must either be located in expensive tunnels or completely covered.
5. Trackways or guideways for past systems have been expensive to build because of needs to provide extensive land grading or massive structural supports for heavy elevated trackways or guideways.
6. Because past automated track or guideway based systems have been designed for relatively short range or low speed operations, they have not been practical for high-speed, long-distance operation. Thus, it is necessary to transfer passengers and cargo between vehicles for transportation over other than relatively short distances.
7. Because of items (1) and (6) above, past rail or guideway based systems using captive vehicles have not provided capability for long-distance, door-to-door service for passengers or cargo.
8. Individual passenger security and privacy are not provided during travel in systems in which relatively large vehicles are used.
9. Automatic point-to-point transportation of cargo is not provided via the same systems providing passenger travel.
10. Systems capable of providing station-to-station passenger service have been unable to accommodate dual mode road use and trackway or guideway use vehicles.
Another system uses special railroad cars equipped with wheel ramps arranged to allow automobiles to be driven onto and off of the railroad car for transport. Such cars and ramps are designed to carry several automobiles over conventional railroads. Ramps are also used at loading and unloading points to allow the cars to be driven onto an off of the rail cars. This system has several disadvantages:
1. The railroad cars are designed to carry a multiplicity of empty automobiles rather than one automobile with passengers.
2. The special railroad cars are designed to operate on conventional railroads rather than on an automated guideway.
3. The ramps for entry and exit of automobiles to the railroad cars are not designed to allow empty railroad cars designed to transport automobiles to pass freely under the entry and exit ramps to reach and leave the automobile loading position.
4. The railroad cars are designed to be pulled by conventional railroad engines as parts of conventional railroad trains rather than operating alone under automated control under their own power and control on an automated guideway system.
Still another system proposed makes use of dual mode cars for both conventional road and guideway use. This dual mode car is conveyed by a monorail and has a set of separate street wheels for street use. This car has a wide, lengthwise section down the center of the car to accommodate the monorail and can only fit passengers on either side of the car. The monorail drive wheels are complex.
What is needed is a single system for rapid and efficient transportation of passengers and cargo both on a door-to-door and station-to-station basis for either short range or long-distance.